From b0ffd5a475f87bf4666870fa2e0001e83d4f0092 Mon Sep 17 00:00:00 2001
From: illiliti <illiliti@protonmail.com>
Date: Wed, 30 Sep 2020 14:15:41 +0300
Subject: [PATCH] Implement StripComponents to rar

---
 cmd/arc/main.go |  1 +
 rar.go          | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/cmd/arc/main.go b/cmd/arc/main.go
index fdb73579..1050cd05 100644
--- a/cmd/arc/main.go
+++ b/cmd/arc/main.go
@@ -235,6 +235,7 @@ func getFormat(subcommand string) (interface{}, error) {
 		v.OverwriteExisting = overwriteExisting
 		v.MkdirAll = mkdirAll
 		v.ImplicitTopLevelFolder = implicitTopLevelFolder
+		v.StripComponents = stripComponents
 		v.ContinueOnError = continueOnError
 		v.Password = os.Getenv("ARCHIVE_PASSWORD")
 	case *archiver.Tar:
diff --git a/rar.go b/rar.go
index 566adef8..56c2a3e3 100644
--- a/rar.go
+++ b/rar.go
@@ -40,6 +40,10 @@ type Rar struct {
 	// especially on extraction.
 	ImplicitTopLevelFolder bool
 
+	// Strip number of leading paths. This feature is available
+	// only during unpacking of the entire archive.
+	StripComponents int
+
 	// If true, errors encountered during reading
 	// or writing a single file will be logged and
 	// the operation will continue on remaining files.
@@ -168,6 +172,17 @@ func (r *Rar) unrarNext(to string) error {
 		return fmt.Errorf("checking path traversal attempt: %v", errPath)
 	}
 
+	if r.StripComponents > 0 {
+		if strings.Count(header.Name, "/") < r.StripComponents {
+			return nil // skip path with fewer components
+		}
+
+		for i := 0; i < r.StripComponents; i++ {
+			slash := strings.Index(header.Name, "/")
+			header.Name = header.Name[slash+1:]
+		}
+	}
+
 	return r.unrarFile(f, filepath.Join(to, header.Name))
 }